---
id: 657f4345abe7f2161f99f1ad
title: الخطوة 16
challengeType: 20
dashedName: step-16
---

# --description--

Start by replacing `pass` with the variable `snake_cased_char_list` and assign it an empty list. Use the square brace notation to create the list but do not put anything between the braces.

Put the braces in separate lines so that you have some space between them, where you can work on the code for the list comprehension.

# --hints--

You should declare an empty list named `snake_cased_char_list` within `convert_to_snake_case`.

```js
({
    test: () => {
        const transformedCode = code.replace(/\r/g, "");
        const convert_to_snake_case = __helpers.python.getDef("\n" + transformedCode, "convert_to_snake_case");
        const { function_body } = convert_to_snake_case;

        assert.match(function_body, /clean_snake_cased_string\s+    snake_cased_char_list\s*=\s*\[\n*\s*\n*\]/);
    }
})
```

# --seed--

## --seed-contents--

```py
def convert_to_snake_case(pascal_or_camel_cased_string):
    # snake_cased_char_list = []
    # for char in pascal_or_camel_cased_string:
    #     if char.isupper():
    #       converted_character = '_' + char.lower()
    #       snake_cased_char_list.append(converted_character)
    #     else:
    #         snake_cased_char_list.append(char)
    # snake_cased_string = ''.join(snake_cased_char_list)
    # clean_snake_cased_string = snake_cased_string.strip('_')

    # return clean_snake_cased_string
--fcc-editable-region--
    pass


--fcc-editable-region--

def main():
    print(convert_to_snake_case('aLongAndComplexString'))

if __name__ == '__main__':
    main()
```
